METHOD OF PRODUCING COMPOSITE MATERIAL Russian patent published in 2020 - IPC C22C26/00 C04B35/52 B24D18/00 

FIELD: chemistry.

SUBSTANCE: invention relates to production of composite material based on diamond particles. Method involves forming a workpiece from a mixture consisting of diamond particles, impregnating the workpiece with molten silicon at temperature of 1420–1500 °C. Diamond particles are represented by cut diamond particles of two fractions - small particles with particle size of 20–28 mcm and large particles with size of 200–250 mcm. Charge contains not less than 60 vol. % of diamond particles with size of more than 200 mcm, and ratio in charge of sizes of particles of small and large fractions is 1:6–1:10. After moulding, workpiece is heat treated in inert gas medium or in vacuum at 700–800 °C. Workpiece impregnation with silicon melt is carried out in vacuum or inert gas medium with formation of cubic silicon carbide and diffusion-reaction Turing process at diamond-cubic silicon carbide interface. Obtained material can be used in designs for various purposes, where it is necessary to combine or dominate one or more of the listed properties: high modulus of elasticity, low density, high hardness and other physical and mechanical properties. When impregnating workpieces from diamond particles of two fractions with liquid silicon, reaction growth of grains of crystalline silicon carbide is provided, which with diamond particles forms a structure corresponding to three times periodic surfaces of minimum energy.

EFFECT: there is provided a material having the following set of physicomechanical properties: density p = 3_2–3_40 g/cm³, elastic modulus E_El = 746–760 GPa and a Vickers hardness HV = 65–70 GPa.

4 cl, 2 tbl, 3 ex, 4 dwg